[php-src] Issue #9687: PHP-FPM memory leak when calling empty static function with object as parameter

Issue: https://github.com/php/php-src/issues/9687 Author: sahl ### Description When I run the following script: ``` <?php // Ten loops for ($i = 0; $i < 10; $i++) { $test = new Test(); $test->test_function(); echo memory_get_usage()."\n"; } class Test { public $data = ''; public function __construct() { } public function test_function() { // Generate 4 MB data inside the object $this->data = str_repeat('a', 4*1024*1024); self::test_function2($this); } public static function test_function2($object) { //echo 'Hello'; // Enable this to prevent memory leak return; } } ?> ``` from the command line interface I get the following output: _4591128 4591160 4591160 4591160 4591160 4591160 4591160 4591160 4591160 4591160_ which is the expected output. (Memory use is constant). When I run it through PHP-FPM I get this output: _4553128 8751608 12950088 17148568 21347048 25545528 29744008 33942488 38140968 42339448_ ...which indicate that memory is leaking. If I enable the echo line, memory will not leak anymore. Tested on PHP 8.1.2 running on Ubuntu Linux 22.04.1 (Sorry I cannot test on newest version, but I have looked through closed issues to see if someone reported something similar). ### PHP Version PHP 8.1.2 ### Operating System Ubuntu 22.04.1